where the loss function \(\mathcal {L}(f(\mathbf {x};\theta ^t), \mathbf {y})\)  consists of a data term \(|f(\mathbf {x};\theta )|\) , an Eikonal term \(|\Vert \nabla _{\mathbf {x}}f(\mathbf {x};\theta )\Vert -1|\) , a normal constraint \(|\nabla _{\mathbf {x}}f(\mathbf {x};\theta )-\mathbf {n}|\) , and an off-surface constraint \(\psi (f(\mathbf {x};\theta ))=\exp (-\alpha \cdot |f(\mathbf {x};\theta )|), \alpha \gg 1\)  following [1]}.
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